Hi
This is a previous post of mine.
Wasserboxer in a Beetle.
The Wasserboxer has received some bad press for headstud problems; coolant leaks and assorted other woes. These problems seem to occur when proper VW servicing techniques are not used.
The Wasserboxer motor in my VW Beetle has been looked after as far correct coolant is concerned; I also use distilled water mixed with genuine VW coolant. I fitted an Oettinger 85° thermostat instead of the standard 87°. These don't seem to be available anymore so I have modified a Mercedes one to fit. The top part of the thermostat is the same as the VW one, but the lower bypass part has a larger diameter flange. This can easily be made the correct diameter by first marking out the correct diameter circle with a pair of dividers and the grind the flange down to the marked circle. I also got rid of water-cooled oil-cooler as I have heard that they can fail. I'm running an air cooled oil cooler with a Setrab thermo block at the front of the radiator.
As far as the rest of the motor goes it is extremely reliable, I give my bug heaps. I have bent one Scat pushrod (I'm now running Berg ones) and had 2 water pumps fail in about 100,000 Ks since 1988 and have had a few coolant hoses fail. My bug is also in constant state of improvement, so some things are always changing.
The Wasserboxers use 2 styles of cooling systems, basically the 1.9 and 2.1 litre style. I prefer the 2.1 style.
Fitting the motor is much the same as fitting a type 4 motor, same style of flywheel. The thermostat housing which sits above # 3 exhaust port needs to have some body clearancing. The water hose that runs from the water pump to the thermostat housing needs to be modified at the water pump end. It basically would run straight through the left-hand rear bumper bracket. Any Beetle exhaust can be used, #1 & # 4 exhaust flanges need to be rotated 90°. In the engine bay I used basically the whole Wasserboxer cooling system and condensed it to fit. You will need a steel coolant ring main as the plastic one cant be shortened easily.
The coolant runs to and from the front of the car via 1.5-inch stainless steel tubes. These follow the chassis bolts along the bottom of the heater channels. I have just upgraded my radiator with a modified Ford Transit radiator. After some gentle prompting from a fellow list user MARTINSR, yesterday I went out and bought an after market thermo fan from Davies Craig
http://www.daviescraig.com.au/. It's meant to be used for a 5 litre V8 and pumps 2120 CFM, so far its working really well, we are having 40 ° + days down here at the moment. I previously used a BMW radiator and Audi 100 thermo fan. Cool air is brought into the radiator through an A/C louvered front apron. I removed the deformation plate at the front of the chassis to allow more air in. I had to also remove the spare wheel well and I just left the rounded edge for a bit of extra strength, I supplemented the spare wheel wells strength with angle steel. My radiator is around 550 mm across and 450 mm deep on the cooling surface, it's actually a little wider where the tanks are on the side. The radiator actually sits on a U shaped holder right down on the chassis and comes very close to the under bonnet. I fabricated a sheetmetal alloy housing to guide the cooling air in and let the heated air exit over the front end. I basically used some angle aluminum for the edges and then filled this in with very thin aluminum sheet. In case you hadn't already realised my bug is a super. I have seen radiators fitted to standard bugs but I have no experience with this. My spare wheel sits on top my fuel tank on a bracket attached to the strut brace.
Original heater channels were retained and warm air is directed from a Toyota troop carrier heater core under the rear seat to the interior via early Audi 100 brake cooling fans. I have used the rear seat heater cable to operate heater shut off valve.
My Kombi motor was purchased new in 1988 and is 2.1 litre its DJ engine number type 10.5:1 compression, 112 BHP type. I original ran the motor with dual webbers Berg cam. In preparation for a turbo the motor has just been decompressed to 8.0:1 and the cam changed back to standard. 1.4 berg rockers are used.
Regards Steve Carter
. And CHEAP!